ARM64: dts: bcm4908: Add BCMBCA peripherals

ARM64: dts: bcm4908: Add BCMBCA peripherals

All the BCMBCA SoCs share a set of peripherals at 0xff800000,
albeit at slightly varying memory locations on the bus and
with varying IRQ assignments. ARM64 SoCs have additional
peripherals at 0xff858000, we extend the peripheral bus
range to 0x400000 to cover this area.

Add the watchdog, remaining GPIO blocks, RNG, and DMA blocks
for the BCM4908 based on the vendor files 4908_map_part.h
and 4908_intr.h from the "bcmopen-consumer" code drop.

This SoC has up to 320 possible GPIOs due to having 10
registers with 32 GPIOs in each available.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: William Zhang <william.zhang@broadcom.com>
Link: https://lore.kernel.org/r/20250512-bcmbca-peripherals-arm-v3-9-86f97ab4326f@linaro.org
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>